Ummm... pretty sure... NEVER. I halved the recipe and made muffins instead of the cake and even with overcooking the muffins a little (the crumb topping got a little TOO crunchy, but still delicious!!!) they turned out yummy. I couldn't stop picking at them... and the little pieces of nuts that stuck out of the topping.
And once I started picking at one of them...
I had a hard time stopping. Too bad I had to use frozen blueberries. These would have been amazing with fresh, in season blueberries.
Check out the recipe at Sihan's Blog.